The present invention relates to systems and methods for controlling the stability of a vehicle and to systems and methods that provide interactive vehicle dynamic control using steer by wire and brake by wire technology.
Brake by wire and steer by wire systems have been developed and continue to be improved to replace conventional vehicle steering and braking systems. Such steer by wire and brake by wire systems have increased versatility and flexibility over standard steering and braking systems that are directly linked to driver input devices such as steering wheels and brake pedals. One of the main benefits of steer by wire and brake by wire systems is that driver inputs may be received and analyzed by a system controller to determine the most appropriate vehicle response given the road and other environmental conditions.
For example, a steer by wire system may be programmed to provide a lesser angular rotation in both magnitude and speed of a road wheel as compared to an angular rotation indicative of the driver""s input on the steering wheel to protect for an under steer or over steer condition. With respect to brake by wire braking systems, for example, these systems modify the driver""s braking input by decreasing or increasing braking force as well as distributing the braking force over all four road wheels to prevent slipping or skidding of the vehicle.
However, prior art steer by wire and brake by wire systems and methods have not been combined to work together to provide overall vehicle stability. For example, typical steer by wire and brake by wire systems work independently of each other to interpret a driver""s input and then independently control the steerable road wheels and the vehicle brakes.
Therefore, there is a need for a new and improved system and method for combining the independent control of the steer by wire and brake by wire systems to achieve an improvement in vehicle stability and performance.